The objective of this proposal is to support the applicant's development of an independent research program focusing on new treatment methods for renal vascular disease with magnetic resonance imaging (MRI) guidance. The candidate's immediate career goals are to gain animal research experience, learn and advance MRI techniques, and enhance clinical skills as an interventional radiologist. The candidate's long-term career objective is to become an active independent biomedical researcher. He aims to improve patient care by expanding the boundaries of MRI from a diagnostic imaging to a treatment guidance modality. To develop his research career, the candidate proposes learning: 1) fundamental MRI techniques related to blood vessel imaging and intervention, 2) swine experimental methods, and 3) methods for the responsible conduct of research. These skills will be acquired through a combination of coursework, MR technique workshops, weekly conferences, independent study, and interaction with sponsors/ advisory committee at Northwestern University Medical School. Sponsors include Drs. J. Paul Finn, Debiao Li, and Robert Vogelzang. The advisory committee also includes Drs. Dieter Enzmann and Francis Klocke. The broad, long-term objective of the research plan is to improve the prognosis of patients with renal vascular disease. In swine, the proposal aims to test the hypotheses that: 1) Intra-arterial gadolinium-enhanced magnetic resonance angiography (MRA) depicts renal arterial lumen caliber as accurately as x-ray angiography; 2) The technical success rate, complication rate, and procedure time for MRI-guided and x-ray guided percutaneous transluminal balloon angioplasty (PTA) of renal artery stenosis are similar; and 3) Successful MRI-guided PTA of renal artery stenosis improves kidney function as measured with MRI at the time of the procedure. If these hypotheses are shown to be correct, then the success and safety for MRI-guided PTA of renal artery stenosis will be confirmed. MRI will be useful to monitor immediate changes in kidney function at the time of renal artery PTA, an added value that cannot be performed using x-ray guidance. MRI guidance will also avoid the ionizing radiation exposure of x-rays and the potential kidney toxicity of iodinated contrast agents.